package szhn.util;

import java.math.BigInteger;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.lang3.StringUtils;

import sun.misc.BASE64Decoder;

public class AesUtil {
	// 密钥
	private static final String KEY = "v587v587v587v587";
	// 算法
	private static final String ALGORITHMSTR = "AES/ECB/PKCS5Padding";

	/**
	 * aes解密
	 * 
	 * @param encrypt 内容
	 * @return
	 * @throws Exception
	 */
	public static String aesDecrypt(String encrypt) {
		try {
			return aesDecrypt(encrypt, KEY);
		} catch (Exception e) {
			e.printStackTrace();
			return "";
		}
	}

	/**
	 * aes加密
	 * 
	 * @param content
	 * @return
	 * @throws Exception
	 */
	public static String aesEncrypt(String content) {
		try {
			return aesEncrypt(content, KEY);
		} catch (Exception e) {
			e.printStackTrace();
			return "";
		}
	}

	/**
	 * 将byte[]转为各种进制的字符串
	 * 
	 * @param bytes byte[]
	 * @param radix 可以转换进制的范围，从Character.MIN_RADIX到Character.MAX_RADIX，超出范围后变为10进制
	 * @return 转换后的字符串
	 */
	public static String binary(byte[] bytes, int radix) {
		return new BigInteger(1, bytes).toString(radix);// 这里的1代表正数
	}

	/**
	 * base 64 encode
	 * 
	 * @param bytes 待编码的byte[]
	 * @return 编码后的base 64 code
	 */
	public static String base64Encode(byte[] bytes) {
		return Base64.encodeBase64String(bytes);
	}

	/**
	 * base 64 decode
	 * 
	 * @param base64Code 待解码的base 64 code
	 * @return 解码后的byte[]
	 * @throws Exception
	 */
	@SuppressWarnings("restriction")
	public static byte[] base64Decode(String base64Code) throws Exception {
		return StringUtils.isEmpty(base64Code) ? null : new BASE64Decoder().decodeBuffer(base64Code);
	}

	/**
	 * AES加密
	 * 
	 * @param content    待加密的内容
	 * @param encryptKey 加密密钥
	 * @return 加密后的byte[]
	 * @throws Exception
	 */
	public static byte[] aesEncryptToBytes(String content, String encryptKey) throws Exception {
		KeyGenerator kgen = KeyGenerator.getInstance("AES");
		kgen.init(128);
		Cipher cipher = Cipher.getInstance(ALGORITHMSTR);
		cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(encryptKey.getBytes(), "AES"));

		return cipher.doFinal(content.getBytes("utf-8"));
	}

	/**
	 * AES加密为base 64 code
	 * 
	 * @param content    待加密的内容
	 * @param encryptKey 加密密钥
	 * @return 加密后的base 64 code
	 * @throws Exception
	 */
	public static String aesEncrypt(String content, String encryptKey) throws Exception {
		return base64Encode(aesEncryptToBytes(content, encryptKey));
	}

	/**
	 * AES解密
	 * 
	 * @param encryptBytes 待解密的byte[]
	 * @param decryptKey   解密密钥
	 * @return 解密后的String
	 * @throws Exception
	 */
	public static String aesDecryptByBytes(byte[] encryptBytes, String decryptKey) throws Exception {
		KeyGenerator kgen = KeyGenerator.getInstance("AES");
		kgen.init(128);

		Cipher cipher = Cipher.getInstance(ALGORITHMSTR);
		cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(decryptKey.getBytes(), "AES"));
		byte[] decryptBytes = cipher.doFinal(encryptBytes);
		return new String(decryptBytes);
	}

	/**
	 * 将base 64 code AES解密
	 * 
	 * @param encryptStr 待解密的base 64 code
	 * @param decryptKey 解密密钥
	 * @return 解密后的string
	 * @throws Exception
	 */
	public static String aesDecrypt(String encryptStr, String decryptKey) throws Exception {
		return StringUtils.isEmpty(encryptStr) ? null : aesDecryptByBytes(base64Decode(encryptStr), decryptKey);
	}

	/**
	 * 测试
	 */
	/*public static void main(String[] args) throws Exception {
		String content = "hello,您好1";
		System.out.println("加密前：" + content);
		System.out.println("加密密钥和解密密钥：" + KEY);
		String encrypt = aesEncrypt(content, KEY);
		System.out.println("加密后：" + encrypt);
		String decrypt = aesDecrypt(encrypt, KEY);
		System.out.println("解密后：" + decrypt);
	}*/
}
